This invention relates to ramps in general to variable and transportable ramps and more specifically to collapsible ramps for wheeled objects.
Transportable and collapsible ramps for wheeled objects such as wheelchairs are known in the art. U.S. Pat. No. 3,818,528 by Petersen shows a pair of tracks laterally hinged to and spaced apart by a center member, the tracks being foldable in upon the center member and the combination being longitudinally foldable. The track length and vertical rise are not adjustable.
U.S. Pat. No. 4,084,713 by Rohrs et al. shows a wheelchair ramp hingably mounted on the floor of an automobile. It comprises a pair of fixedly space tracks longitudinally foldable. U.S. Pat. No. 3,176,334 by Lovdahl shows a very similar ramp. Likewise U.S. Pat. No. 4,127,201 by Baumann shows a collapsible ramp comprised of a pair of longitudinal supports secured to and supported by a vehicle for the purpose of loading and unloading wheeled objects. In all the above cases the track lengths not adjustable and the tracks themselves are not self-surpporting.
U.S. Pat. Nos. 3,315,292 by Collins and 3,936,898 by Poe both show hinged together plates of rectangular configuration with vertical members for a self-supported rise. They are not longitudinally nor laterally adjustable in dimension.
This invention addresses in particular the problem of providing a lightweight ramp for persons confined to a wheelchair which is adaptable to a wide variety of ramping requirements. For example, this invention can be used to ramp a wheelchair in or out of a vehicle, up or down a street curb, and up or down a small flight of stairs. It is adjustable in length and width, it is self-supporting, and it is adjustably variable in its vertical rise. Furthermore it is collapsible and can be easily carried by a wheelchair.
Other advantages and attributes of this invention will be readily discernible upon a reading of the text hereinafter.